Rotating fuel element reactor pump



April 18, 1961 c. A. COOMBS 2,980,667

ROTATING FUELELEMENT REACTOR PUMP Filed Oct. 51, 1958 2 Sheets-Sheet 1 V i 5 /j INVENTOR.

E15. 1. cHADW/CK A. COOMBS BY k/WM A TTORNE Y April 18, 1961 c. A. COOMBS ROTATING FUEL ELEMENT REACTOR PUMP iled 00$. 31, 1958 2 Sheets-Sheet 2 INVENTOR. CHADW/CK A. COO/WES ATTORNEY which, provides a wet betested. Y

2,980,667 I ROTATING FUEL ELEMENT REACTOR PUMP i Chadwick A. Coombs, Washington, D.C.', assignor, by mesne assignments, to Allis-Chalmers Manufacturing -Company, a corporation of Delaware Filed Oct. 31, 1958, Ser. No. 770,972

Claims. (Cl. 204-1932) Thisinvention relates to nuclear. reactors and, more particularly, to research reactors designed for the purpose ofrcondueting experiments to gain information. Reactors of this type produce a large supply of neutrons and gamma rays for. research, such radiations being used at the core of the reactor where they are produced or outside the reactor where they are led by special openings built into the reactor structure. Conventional research reactors are provided with 'a core of fuel, elements, eachv comprising a plurality. of spaced, enriched uranium fuel plates enclosed within a tubular housing. During operation, light or heavy water is circulated through the fuel elements to .serve'asIa c'oolant and neutron moderator. v.In tank type reactors, the yvateriis usually directed into a plenum chamber and thence V eupwa'rdly in equal quantities through the several fuel elements forming the reactor core and, as a result thereof,

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ment of fuel elements within the reactor core, and commeans for rotating the fuel elements. I

Fig. 3 is afragrnentary view in-which the several fuel elements are provided within individual driving motors.

Referring now to the drawings for a better understanding of the invention, each fuel element 5 is shown as comprising a coil of fissionable material defining a helical fuel plate 6 havingits inner peripheral edge secured to a shaft shown as an imperforate central tube 7 formed of aluminum or stainless steel. The outer peripheral edge of the fuel ;plate is secured to an outer imperforate tube -8 formed of aluminum or stainless steel. The helical fuel plate in this arrangement defines a spiral portion disposed between imperforate wallmembers to provide a helical passage therebetween. I

To provide a fuel element of a size corresponding generally to the size of a conventional MTR fuel element, the outer diameter of the central tube 7 may be one inch, the inner diameter of the outer tube 8 may be 4 inches, and the length of the outer tube and helical fuel plate therein may be approximately '23, inches. To provide a volume of fissionable material corresponding to the volume of fissionable material in the fuel plates in the MTR fuel element, the helicalfuel plate 6 may have a thickness of 0.060 inch and a pitch of 0.20 inch. The fuel Each fuel element 5 is journaled on its axis for rotation.

As shown in Fig. l, a tubular stainless steel inlet nozzle 9 is secured to the lower end of the central tube 7 andjournaled in a bearing 11; provided on a; plenum outlet nozzle 12 formed with radial vanes 13 for directing operated at a substanofhelical form mounted for rotational movement to serve as anaxial fiow pump to move the liquid moderatoriand "coolant through the fuelelement. A'furtherobject ofthe invention resides in the provision of .meansfor rotating a core of fuel platesiatdifcoinpiises a plurality offuel'elemeuts. spaced, for exferent speeds-to maintainthe several fuel plates at='a inuhstantially; equal temperature during operation of the reactor.

;atAnotherobjectis to provide'a fuel element for a tank .-,tYP6 ,resea'rch reactor containing light or heavy .watertas 3 amoderator and cooling, wherein the fuel element ac'ts,

asya pump to, move the water from a plenum chamber nandthrough the fuel element into the tank. f

Another object is:.to provide a fuel element wherein a helical fuel, plateis securedto arotatable central tube irradiation facility for materialsto eyAnother-object of-the invention is to p rovide a fuel element embodying a-single helical fuel'plate having'an fuel element of theMTR- type." i

The invention embodies othernovel area and volume equal to 18 fuel plates in a conventional features, details of construction and'a rrangefnent of parts which are hereinafter set forth'in'the specification and claims and illus ,trated,in-,t,he accompanying drawings, forming part thereof, wherein: if I v v V Fig. 1 is a fragmentary vertical section of a tank type ,yheterogeneous ,.lJl.1Cl6,aI..I6aClOl1 'provided with. aaeore of fuel elements embodying featuresof the invention.

Fig. 2 is a schematic plan view illustrating thearrangefluid upwardly through the fuel element. The upper end of the central tube'7 isshown as journaledina bearing 14 provided ,on a removable plug 16 normally seated in an opening 17 formed in a lower shield plug 1 8,ofa conventional heavy water moderated reactor 19.

. 'lfhe reactor19 is shown as-comprising a tankjzl provided with aplenum chamber 22 and a plenum wall.23 formed with ports 24 for the passage of moderating and cooling liquidto the fuel elemen'ts. The tank is provided wit h a liquid 9utletcpnduit 26 leadingto a heat exchanger :27 having a. conduit lls leading to theplenum chamber 7 As illustrated;schematically. in Fig. 2,- the reactor core ample on sixjnch centers to provide a'central fuel element:5a.e nclosed within an inner circleof fuel elements 5b and an outer 'circle of fuel elements 5c. A pulley '29 ing through an endl ess belt 32. Pulleys 33 are secured to the upperendsof the central tubes 70f the fuel ele- 'ments Sc forengagementby a common belt34.

;.A pulley secured to a fuel element Sc'acts through a belt3g7 to drive a, relatively smaller diameter pulley ,38 secured to the fuel elements 5b. Pulleys 39 are secured to; the fuelelements 5b for engagement by a common endless belt 41. J A pulley 42 secured to a fuel element 5!; acts through a, belt A3, to drive a relatively smaller i meter pulley 44,.seoured to the fuelelement 5a. By means of the pulley and belt arrangement, thus shown and described, itwill be noted thatthe fuel elementsrib ;will rotate faster than the fuel elements 50; and that the fuel, element 5 will rotatefaster than the fuel elements 1 I illustrates a modified 'form 'lof the ,invention wherein each fuel element 5 within a reactor core is driven by its individual yariable-speedelectric motor 46fcon-.

trolled by individual rheostats '47; whereby the 1 fuel -;elements may-be rotated at different speeds for increasing or decreasing the flow of coolant therethrough to mainiofnuclear reactors; a

the plenum chamberIZZ andthroughethe I V defined in the fuel elements intothe o tank 21, the liquid; being returned from "the tain the temperature of the several :fuel plates 6 within predetermined limits. I

The invention shown I Ofiice :of Technical Services, US; Departmentof Commerce, Washingtom D,C., and the disclosmetherein is incorporated herein by reference, *However it i's ap- I rotational movernent therein, said fuel element compris- I I and'a spiral fissionable partition therebetween so as to provide a helicalfiuid passage having inlet and outlet I merged within said liquid and journaled on its axis for tag radially inner and outer imperforatewall members 1 openings at the axiallyopposite ends. respectively of said parent that the invention is adapted for use in other types During operation, the

itated in a direction to cause the-helical 'fuel pla'ts 6 to draw the liquid coolant and. moderator upwardly from plenum chamber through'the conduit'sl'zfi and 28.- I The Plieal passage 1 end of the I ;tank to the severalfuel elements 5 are rofuel'element, anddrive'means for rotating said fuel ele- I ment on said axis and thereby cause circulation of said liquid-through said passage,

fuel elements; submerged within said l iqui d, with each element journaled on itsaxis forrotational movement therein, each fuel element embodying a spiral fission-able member and associated radially inner and outerimper' forate wall members affording a helical passage for the.

, circulation of: said liquid 'therethrough upon rotational movement ofthe fuel element, and means to rotate the several fuel elements at diiferent relative speeds,

, I I liquid is free to circulate upwardly through the central tubes '7 and outwardly'therefrornthroughthe outlet openlugs 48. By removing the plug' '49.fromthe upper end I iimitation; the scope of the invention being set forth ,in the following claimsz' I I t I I What is claimed is:,

inletrand outlet openings, respedtivel fat its opposite ends, and means mounting said fue' l element forrotational movement thereof on the axis of said, cfoil; said liquid, inlet and outlet openings communicating with said liquid so that movement of said fuel veleiiientayvillcause said.

liquid to circulate through said passage. I I I 2. In a heterogeneous nuc lear reactor' containing a moderating and cooling liquid, a fuel-elementcomprising a coil of fissionable material and wall' meansassociated tcomprijsing of a central tube 7, a thirnble' or capsule containing ma- I 'teria'l may be lowered into the tubefor conducting ir- I radiation experiments within a high lluig zonejin the fuel; 2 I element or core'of elements. Q I 1 Having described apreferred embodimentof pres I eat invention, it'is'to'be understood that although specific 5 @terms and examples are employed, they are used in a I generic and descriptive sense and not forpurposes of I movementof the fuel element, and common-drive means I to rotategtheseveral fuel, elements at dilferent relative I .7; Ina heterogeneousnuclear reactor, a tank containa moderating and cooling liquid, a core of tubular.

fuel elements submerged within'said liquid, with each element journaled on its axis for rotational, movement therein-each fuel element embodying a spiral jfissionable member and associated radially inner and outer impede: rate wall members, affording a helical passage for the circulation. of said liquid :therethrough ,upon rotational speeds. II

urfuel elements submergedwithin-said liquid, with each therewith so as to define a spiral passage having liquid I inlet and outlet openings, respectively, at its oppositeii ends, and means mounting said fuel element submerged within said liquid for rotational movement on theiairis of said coil and means to rotatesaid fuel element'on its axis in a direction so as tocause circulation of said liquid throughsaid passage.

3. In a' nuclear reactor plate containing fissionable material, a shaft secured to the inner peripheral edge. of said plate, an imperforate tubular member secured t6 the outer peripheraledge of rust element, -a vague-i1 fuel said plate, said fuel plate, shaft, and tubular memberde- 2 fining an open ended helicalpassage lforfthe 'flowjof liquidtherethrough. V i I I v 4. In a heterogeneous nuclear reactor: containing amoderating and cooling liquid, a tubular fuel element submerged within said liquid, and journaled on its axis for rotational movement therein, said fuel element cofnprising radially inner and outer imperfora'te wall members and a spiral partition therebetween so as to providefa helical fluid passage having inlet and outlet openings at the axiallyopposite ends, respectively; of said fuel element; and drive means for-rotating said fuel element on said axis and thereby cause circulation-ofsaid liquid through said passage. I I

5. In a heterogeneous nuclear reactorcontaining a moderating and cooling liquid, a tubular fuel element subelement journaled on its axis for rotational movement I I therein; each fuel element embodying a spiral fissionable member and; associated radially, inner. and outer imperfo 'ratewall members affording a'h'elical passage for the circulation of said-liquid therethrough upon rotational speeds. I I t 9. In a heterogeneous nuclear reactor, a tank containing a moderating and cooling liquid, a core oftubular fuel elements submerged within said liquid, with each element journaled on its axis for rotational movement therein, l each fuel element embodying a spiral fissionable member .anda'ssociated radially inner and outer imperforate wall members affording a helical passage for the circulation of said liquid therethrough upon rotational movement of the fuel element, said tank having a plenum chamber provided with ports for the flow of liquid upwardly through ..the several fuel elements, andmeans to recirculate liquid from the tank to the plenum chamber.

.10. In a heterogeneous nuclear reactor, a tank con- ,taining a moderating and cooling liquid, a core oftubular fuel elements submerged within said liquid, with each References, Cited in the file of this patent UNITED STATES PATENTS 2,812,304 Wheeler Nov. 5, 1957 FOREIGN PATENTS,

797,608 Great Britain July 2, a

6. In a heterogeneous nuclear reactor, a tank contain- I ing 'a moderating and cooling liquid, acore of tubular '8. In a heterogeneous nuclear reactor, atank containv ing a morlerating and cooling liquid,'a core of tubular I fI JNITED STATE-S PATENT OEFICE CalllIi'I',I'FIGATE 6F CORRECTION Patent No; 2,980,667 April 18 1961 Chadwick A. Coombs It is hereby cepfiified that error appears in the abeve numbered petent requiring correction .and that the said Letters Patent. should read as "corrected below.

Column 3 line 43, after that. insert rotational Signed'and sealed this 19th day'of September 19611,

(SEAL) Attest:

ERNEST 1w. swine- DAVID L. LADD Commissioner of Patents Attesting Officer I v uscoMM-oc I :IUNITED STATES PATENT OFFICE l CERTIFIGATE OF CORRECTION Patent No; 2,980,667 Apr-'11 l8 1961 Chadwick A. COombs It is hereby-certified that error appears in the above numbered patent requiring correction and that the said Letters Patent. should reed as "corrected below.

line 43, after "that" insert rotational Column 3,-

s 19th day'of September 1961,

Signed and sealed thi (SEAL) Atteet:

ERNEST w. :swmm DAVID L. LADD Commissioner of Patents Attesting Officer uscoml oc 

1. IN A HETEROGENEOUS NUCLEAR REACTOR CONTAINING A MODERATING AND COOLING LIQUID, A FUEL ELEMENT COMPRISING A COIL OF FISSIONABLE MATERIAL AND WALL MEANS ASSOCIATED THEREWITH SO AS TO DEFINE A SPIRAL PASSAGE HAVING LIQUID INLET AND OUTLET OPENINGS, RESPECTIVELY, AT ITS OPPOSITE ENDS, AND MEANS MOUNTING SAID FUEL ELEMENT FOR ROTATIONAL MOVEMENT THEREOF ON THE AXIS OF SAID COIL, SAID LIQUID INLET AND OUTLET OPENINGS COMMUNICATING WITH SAID LIQUID SO THAT MOVEMENT OF SAID FUEL ELEMENT WILL CAUSE SAID LIQUID TO CIRCULATE THROUGH SAID PASSAGE. 